考虑高墩二阶效应的简化迭代计算方法

为快速计算高墩侧移所致的二阶效应，在经典解析法的基础上，提出一种新的计算高墩二阶效应的简化迭代方法.根据高墩与上部结构的不同约束情况，推导建立相应的迭代计算公式.将简化迭代算法分别应用于一座高墩连续刚构桥和一座高墩连续梁桥算例中，并将计算结果与有限元法计算结果进行对比.结果表明，经过4次迭代计算后，本方法即可达到收敛条件；对于高墩连续刚构桥算例，墩顶水平位移和墩底弯矩的简化迭代计算结果与有限元模型计算结果的相对误差分别仅为-0.11%和-1.18%;对于高墩连续梁桥算例，两者相对误差分别仅为1.04%和1.02%.

A simplified iterative calculation method for second-order effect of tall pier

To quickly calculate the second-order effect of the bending moment of the tall pier, a new simplified iterative calculation method considering the second-order effect of the bending moment of the tall pier is proposed based on the classical analytical method. According to the different constraints of the superstructure, the corresponding iterative calculation formulas were deduced and established. The simplified iterative algorithm was applied to a continuous rigid frame bridge and a continuous girder bridge, both with tall piers, respectively, and the calculation results were compared with the numerical results by finite element (FE) method. The results show that the method proposed in this paper can reach the convergence condition after three iterations, and the errors between the calculation results and the numerical results of the horizontal displacement at top of the tall pier and the bending moment at bottom of the tall pier are only +2.62%, -0.09% (for the continuous rigid frame bridge) and -0.04%, - 0.11% (for the continuous beam bridge), respectively. The application example shows that the simplified iterative algorithm proposed in this paper can quickly and accurately calculate the second-order effect of bending moment of tall pier.